With spring practice starting at Penn State, it's a good time to look at early projections for the upcoming season. The defense, which finished fourth in the Big Ten last year in total defense, should once again be solid, despite losing five starters.

Even though the losses of big names such as Gerald Hodges, Jordan Hill and Michael Mauti, leave big holes to fill, the Nittany Lions have capable replacements with plenty of experience.

The 2013 squad has the luxury of having both returning starters and young talent that should put up good numbers this season.

Defensive end Deion Barnes and cornerback Adrian Amos will be leaders on the defense and are sure to be two of the statistical leaders on the defensive side.

While it's still early, the following slides project numbers for the players who will lead the team in each of four defensive statistical categories for the 2013 season.

Total Tackles: Mike Hull

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2013 Prediction: 95 Total Tackles

Mike Hull has the tough task of taking over for the departed Michael Mauti in 2013, who was second on the team last year with 95 tackles. Hull will be needed to play an important role on defense in the upcoming season.

Based on what he has shown so far, Hull is more than capable of handling the task. As a backup in 2012, he recorded 58 tackles.

Hull made 16 tackles in the final two games while replacing Mauti due to injury. He will be a starter when the season begins, and will have plenty of opportunities to record tackles from the outside linebacker position.

With plenty of experience, having played in every game since the 2011 season, Hull will be looked to as a leader on defense this year. He will be a full time starter for the first time in his career and will continue the Penn State tradition of great linebackers.

Middle linebacker Glenn Carson, who made 85 tackles last year, will challenge for the top spot in that category, but look for Hull to win in a close race.

Sacks: Deion Barnes

Defensive end Deion Barnes had a fantastic year in 2012. He started eight games as a true freshman and was a key part of the Nittany Lions' defense.

Barnes finished the year with 26 total tackles and led the team with six sacks and 10 tackles for loss. That performance earned him Big Ten Freshman of the Year honors.

2013 should once again see him lead the team in sacks. However, Barnes will need to step up his game, as he will now have more attention paid to him. Last season, All-Big Ten defensive end Jordan Hill drew much of the attention from opposing blockers. With Hill gone, Barnes could see more double-teams from opponents.

There's no question he will be the biggest target of opposing linemen due to his talent. Despite the extra attention, Barnes will still have opportunities to break free and wreck havoc on quarterbacks.

Tackles for Loss: Anthony Zettel

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2013 Prediction: 10 Tackles for Loss

Though Deion Barnes led the team in this category in 2012, Anthony Zettel will take over this year. With Barnes likely being a bigger target for offensive linemen, Zettel will find opportunities to break free and get into the backfield.

Last season as a redshirt freshman, Zettel played in every game and showed an ability to get into the backfield. Though he made only 15 tackles, four of them were for a loss. All four ended up being sacks, with two coming in the game against Navy.

Zettel is a bit under the radar and could surprise several opponents in 2013. After mainly filling in at end last season, a move to defensive tackle to take over for Jordan Hill seems to be in the cards.

He's in line to see significant minutes as a starter this year and will look to improve his already solid numbers.

Look for Zettel to take a giant step forward this year and develop into a key component of the Penn State defense.

Interceptions: Adrian Amos

Adrian Amos enters his junior year with a ton of experience and will be a leader on a defense that losses five starters from a year ago.

The cornerback has played in every game since he's been in Happy Valley and started all 12 games last season. He finished 2012 with 44 tackles. He led the Nittany Lions with two interceptions.

Amos has developed into a top cornerback in the conference who is almost always locked with the opposing team's best receiver. That means that he sees plenty of action during a game, with a lot of passes being directed his way.

With a lot of roster turnover in the front part of the defense for 2013, the secondary, which returns three starters will need to step up. Amos is quick and athletic and will be the star of the Penn State defensive backfield this year.